Definition of achromatic lens in English:

noun

After improvements in the microscope, especially the 19th century development of the achromatic lens, and dissemination of the cell theory by Virchow in 1858,2 the level of analysis descended to the microscopic or cellular level.

The objectives are adopted by poly-membrane achromatic lenses and collocated with widefield eyepieces.

It consists of two identical achromatic lenses, placed with their most curved surfaces facing each other.